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OBJECTIVES: This study aimed to assess the influence of translucent monolithic versus bilayered crowns and whether the use of a CoCr base abutments affects the fatigue and fracture resistance of screwed implant-supported single crowns with external connections under mechanical cycling. MATERIALS AND METHODS: Fifty specimens were divided into groups: (1) metal-ceramic (MC) crown, (2) veneered zirconia crown (Zr), (3) veneered zirconia crown with a CoCr base abutment (ZrB), (4) monolithic translucent zirconia crown (MZr), and (5) monolithic translucent zirconia crown with a CoCr base abutment (MZrB). Specimens underwent mechanical cycling (5 × 106 cycles; 150 N) evaluating fatigue resistance (number of failures) and those that failed were subsequently subjected to fractographic analyses (stereomicroscope and scanning electron microscope) to evaluate failure location and area, and maximum fracture load was also measured. RESULTS: The failure-related survival rate (100%) and maximum fracture resistance of the MZrB were significantly higher than those of MC and Zr (50%; p < 0.05). There were no significant differences in the failure rate and fracture resistance when a CoCr base abutment was used or not in the translucent monolithic Zr groups (p > 0.05;MZrB vs. MZr). Failure location, with MC crowns' fractures, noted at the screw area (p = 0.043), while all-ceramic crowns were mostly in the cuspid and to failure area, the Zr group had the largest mean (15.55 ± 9.17 mm2) among the groups, significant difference only when compared with MC (1.62 ± 0.81 mm2) (p = 0.025). CONCLUSIONS: Translucent monolithic zirconia crowns exhibited significantly higher fatigue and fracture resistance compared with conventional MC and bilayered crowns. CLINICAL SIGNIFICANCE: The appropriate choice of material and manufacturing technique is crucial for predicting the higher clinical performance of single crowns. Enhanced mechanical resistance in terms of fatigue and fracture resistance can be achieved by replacing MC and bilayered restorations with computer-aided design and computer-aided manufacturing monolithic zirconia.

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Background: The aim of this systematic review is to determine the effectiveness of self-etching primers in comparison to the conventional protocol with hydrofluoric acid and silane treatment for bonding lithium disilicate ceramics. Material and Methods: The formulated PICO question for this research was: "Does self-etching silane primer surface treatment in lithium disilicate ceramics present a similar bond strength value compared to conventional hydrofluoric acid and silane treatment?". Combinations of words and appropriate truncations were adapted for each database. For the selection, duplicate articles were systematically eliminated using Mendeley software. The Cohen's Kappa statistic was then computed, RoBDEMAT questions were addressed, and the meta-analyses were conducted using RevMan 5.4, at a significance level of 5%. Results: Two independent reviewers conducted a blind and independent analysis of 190219 articles from PubMed, Scopus, Web of Science, and OpenGrey. Subsequently, they extracted data from 21 studies for the systematic review and in 16 the meta-analysis. In all in vitro studies, the most frequently cited concentration of hydrofluoric acid was 5%. In the meta-analysis, no statistical differences were observed between the two treatments concerning bond strength. Conclusions: Self-etching silane primers demonstrate promising results in lithium disilicate bonding, suggesting their potential as an alternative surface treatment to hydrofluoric acids + silane. Key words:Lithium disilicate, Hydrofluoric acid, Dental Porcelain, Ceramics, Silanes.

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This study aimed to compare the mechanical properties of various occlusal plate materials by analyzing surface roughness, Knoop microhardness, flexural strength, and modulus of elasticity. Fifty samples were prepared and classified as SC (self-curing acrylic resin), WB (heat-cured acrylic resin), ME (acrylic resin polymerized by microwave energy), P (resin print), and M (polymethylmethacrylate polymer block for computer-aided design/computer-aided manufacturing). The data were analyzed using a one-way analysis of variance and Tukey's honestly significant difference test. Surface roughness was the same in all groups. The surface hardness of group M was statistically superior. The samples from groups P and M had higher flexural strength than other samples. The modulus of elasticity of group SC was statistically lower than that of other groups. The mechanical properties of the materials used to make the occlusal plates differed, and group M achieved the best results in all analyses. Therefore, clinicians must consider the material used to manufacture long-lasting and efficient occlusal splints.

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Abstract This study aimed to compare the mechanical properties of various occlusal plate materials by analyzing surface roughness, Knoop microhardness, flexural strength, and modulus of elasticity. Fifty samples were prepared and classified as SC (self-curing acrylic resin), WB (heat-cured acrylic resin), ME (acrylic resin polymerized by microwave energy), P (resin print), and M (polymethylmethacrylate polymer block for computer-aided design/computer-aided manufacturing). The data were analyzed using a one-way analysis of variance and Tukey's honestly significant difference test. Surface roughness was the same in all groups. The surface hardness of group M was statistically superior. The samples from groups P and M had higher flexural strength than other samples. The modulus of elasticity of group SC was statistically lower than that of other groups. The mechanical properties of the materials used to make the occlusal plates differed, and group M achieved the best results in all analyses. Therefore, clinicians must consider the material used to manufacture long-lasting and efficient occlusal splints.

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Background: To evaluate the stress distribution of three-element prostheses on two different implant systems (External Hexagon (EH) or Morse Taper (MT)) and with two different retention mechanisms (screw-retained or cemented), by photoelastic analysis and strain gauge analyses. Material and Methods: Four photoelastic and 24 strain gauge models of a partially edentulous maxilla were made and were divided in four groups according to connection and retention system: Group I (EH-C) - external hexagon+cement-retained prosthesis; Group II (EH-S) external hexagon+screw-retained prosthesis; Group III (MT-C) - morse taper+cement-retained prosthesis; Group IV (MT-S) - morse taper+screw-retained prosthesis. The implants were installed in the axial position, the first in the region of element 15 and the distal implant in the region of element 17. Loads of 100 N were applied on the occlusal surface of the prosthesis for 10 seconds. For the photoelasticity analysis, photographic images were taken and were evaluated according to the number of high-intensity fringes. For the strain gauge analysis, the strain gauges were positioned on the marginal crest of the implants and on the apical region, being numbered for analysis of the stress distribution in each region. The electrical signals were captured and processed by specific software. Results: Higher concentration of tension was observed in the apical region of the implants and mainly in the distal implant, where the formation of fringes was higher. The microstrain values obtained for each group were similar: EH-C (454±18,3 µÉ›); EH-S (469±94 µÉ›); MT-C (466±49,8 µÉ›); MT-S (460±36,6 µÉ›). It was observed that apical position had higher stress concentrations for all analyzed groups. Conclusions: The different connections and fixation mode did not interfere in the amount of tension generated in the tissue adjacent to the implant, also the region that generated the greatest amount of tension was in the apical region of the anterior implant. Key words:Dental implants, biomechanics, fixed prosthodontics.

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OBJECTIVE: The aim of this study is to verify whether removable dentures of patients admitted to an intensive care unit (ICU) are niches of microorganisms that can cause pathologies (Staphylococcus aureus, Candida spp., and enterobacteria). MATERIALS AND METHODS: Fifteen patients who were denture wearers (removable partial denture and complete denture) were included in this study. Patients must wear their dentures daily, and these dentures must have acrylic parts. Microbial biofilm was collected from the acrylic part of one denture of each patient. Then, the biofilm was seeded on different culture media: Sabouraud agar, blood agar, MacConkey agar, and mannitol salt agar. In this study, biochemical evaluations of microorganisms were performed. STATISTICAL ANALYSIS: The percentage of dentures with the microorganism identified by each culture medium was calculated. RESULTS: In total, 100% of the dentures were positive for Staphylococcus spp. (blood agar) and Candida spp. (Sabouraud agar); 33.3% of the dentures were positive for S. aureus (Mannitol salt agar); and 13.3% of the dentures were positive for Shigella spp. (MacConkey agar). CONCLUSION: Removable dentures of patients (removable partial dentures and complete dentures) admitted to an ICU are niches of microorganisms that can cause pathologies.

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STATEMENT OF PROBLEM: Although recent studies have reported the success of implant-supported monolithic restorations, consensus on the use of monolithic ceramic restorations is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the survival and biological and technical complication rates of monolithic single crowns and fixed partial dentures (FPDs). MATERIAL AND METHODS: An electronic search was conducted by 2 independent authors on the PubMed/MEDLINE, Scopus, and Cochrane Library databases. The Newcastle-Ottawa scale and Cochrane risk of bias tool were used to assess the quality and risk of bias of the included studies. Meta-analysis was performed by using the R software program. RESULTS: The search identified 763 articles, 18 of which met the eligibility criteria. A total of 15 studies evaluated monolithic ceramic single crowns, and 4 studies evaluated FPDs. The studies included 1061 monolithic single crowns (524 lithium disilicate, 461 zirconia, and 76 polymer-infiltrated ceramic network [PICN]) and 104 FPDs (36 lithium disilicate and 68 zirconia). Meta-analysis of single-arm studies indicated the proportion of survival, biological, and technical complication rates of 1% (95% confidence interval [CI]: 0% to 3%), 1% (CI: 0% to 4%), and 2% (CI: 1% to 4%), respectively, for single crowns, independent of ceramic material, and 3% (CI: 0% to 34%), 5% (CI: 1% to 21%), and 5% (CI: 1% to 21%) for FPDs, respectively. Only 5 studies performed a direct comparison between monolithic and veneered ceramic restorations, and no significant difference was observed in terms of survival (risk ratio [RR]: 0.68; CI: 0.25-1.91; P=.96), biological (RR: 0.69; CI: 0.31-1.53; P=.35), and technical complication rates (RR: 0.87; CI: 0.40-1.88; P=.29). CONCLUSIONS: The use of monolithic ceramic can be considered a favorable treatment for tooth-supported single crowns and FPDs, with high survival and low complication rates. However, further randomized controlled trials are needed to reassess these clinical performances, mainly by comparing them with the performance of veneered restorations.

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OBJECTIVES: To characterize the surface of zirconia (Y-TZP) submitted to different surface treatments (with and without plasma associations) and to evaluate the shear bond strength (SBS) between veneering ceramic (VC) and Y-TZP after different aging methods. METHODS: 301 Y-TZP specimens were fabricated and distributed into 7 groups: C (control): no treatment; Al: airborne abrasion with 27 µm Al2O3 particle; L: liner; P: plasma; Al + L: airborne + liner; Al + P: airborne + plasma; P + L: plasma + liner. The Y-TZP surface was characterized by SEM, EDS, AFM, surface profilometry, surface-free energy (SFE), and XRD. SBS between Y-TZP and VC was verified after three aging protocols: initial, after hydrothermal aging (autoclave for 5 h), or thermal fatigue (30,000 baths - 5-55 °C). One- (profilometry, SFE) and two-way ANOVA (SBS), and Tukey's HSD test were used. RESULTS: For the plasma groups, a full globular surface coverage was observed (SEM, AFM). Si was found for Al, L, Al + L, and P + L. Roughness was lower for C, P, and Al + P. For SFE, the highest values were found when the liner was applied (>74.59 nm/Nm). The highest monoclinic content was observed for Al + L (6.96%) and Al + P (5.86%). For the initial period, Al and P + L presented the lowest SBS values (<5.85 MPa; P > 0.331). The highest SBS values were found for L, P, and P + L (hydrothermal aging) and for P, L, Al + L, and Al + P (thermal fatigue). SIGNIFICANCE: Changes in Y-TZP topography and the SBS with the VC were found, according to treatments performed. Plasma treatment improved SBS and did not cause phase transformation.

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Aim: This systematic review with meta-analysis aimed to evaluate the effect of the laser treatment on bond strength between Y-TZP and the resin cement or with the veneering ceramic, and the effect on the alteration of the Y-TZP surface roughness. Settings and Design: Systematic review and meta analysis following PROSPERO guidelines. Materials and Methods: A comprehensive review was performed up to September 2020 on four databases (PubMed/MEDLINE, Embase, Scopus, and Cochrane Library), using the combination of keywords: "laser AND zirconia AND surface treatment AND bond strength". Statistical Analysis Used: The meta-analysis was based on the Mantel-Haenszel and inverse variance methods. The continuous outcome was evaluated by mean difference and the corresponding 95% confidence intervals. Results: A total of 37 studies were identified for the inclusion of data, with only in vitro studies. The types of laser reported in the studies were: Er:YAG, Nd:YAG, Er,Cr:YSGG, CO2, Femtosecond, and Yb lasers. A random-effect model found statistically significant differences between lasers and control groups of Y-TZP (P < 0.00001; MD: 3.08; 95% CI: 2.58 to 3.58). Only the bond strength with the Er:YAG laser did not present statistical difference (P = 0.51; MD: 0.22; 95% CI: -0.44-0.88). In another analysis, a random-effect model found a statistically significant difference between the laser and control groups on surface roughness (P < 0.00001; MD: 0.96; 95% CI: 0.86 to 1.06). Conclusions: Laser irradiation is capable to improve the Y-TZP surface roughness and the bond strength of zirconia with resin cement and veneering ceramics. However, there is a lack of laser protocol for the zirconia surface, a fact that makes a simple and direct comparison difficult.

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OBJECTIVE: To evaluate the optical, chemical, and mechanical properties of feldspathic porcelain after handling with different instrument materials. MATERIAL AND METHODS: Feldspathic porcelain was manipulated with different spatula compositions: metal spatula (MS), plastic spatula (PS), and glass spatula (GS) for the fabrication of 30 (n = 10) disks. Contrast ratio (CR), translucency parameter (TP), and surface Knoop microhardness (KHN) were measured. The color change (ΔE00 ) was evaluated using the CIEDE2000 system. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) were used for surface analysis. Data were analyzed using one-way ANOVA and Tukey test (P < 0.05). RESULTS: All groups presented different morphological surfaces with higher presence of Al on the MS. PS group presented lower Al, Si, K than MS, and GS. Higher CR was observed for PS (0.734; P < 0.043), followed by MS (0.696; P < 0.043) and GS (0.65; P < 0.011). The highest TP (13.06) and KHN (386.27) were presented by GS (P < 0.001). MS and PS presented similar KHN results. The higher ΔE00 were found for plastic/metal comparison. Also, the L* values for the MS group (67.49) were lower than the other groups. CONCLUSION: The use of metal spatula promoted higher color alteration during feldspathic porcelain manipulation than did the other materials. Handling with glass instrument promoted higher microhardness than other spatula materials. CLINICAL SIGNIFICANCE: The effect of the material used for ceramic handling on feldspathic porcelain properties is often ignored. This study shows that the handling spatula material must be carefully chosen to avoid inadvertent changes to the feldspathic porcelain restoration.

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OBJECTIVE: To evaluate the influence of different pigmentations and accelerated aging on the hardness and tear strength of the A-2186 and MDX4-4210 silicones. MATERIALS AND METHODS: The samples A-2186 and MDX4-4210 were manufactured without and with pigmentations (black, bronze, and pink). For the Shore A hardness test, 80 samples of each silicone were fabricated, and for the tear strength test, 320 samples of each silicone were fabricated. Eight groups were created for each test (n = 10). These tests were performed before and after 252, 504, and 1008 hours of aging. Three-way repeated-measures analysis of variance and the Tukey test were performed (α = 0.05). RESULTS: The A-2186 silicone showed higher hardness and tear strength when compared with the MDX4-4210 silicone (p < 0.05), except in the hardness of the A-2186 and MDX4-4210 groups without pigmentation after 1008 hours (p > 0.05). All hardness values were between 25 and 35 units, regardless of the silicone type, period, and pigmentation (or no pigmentation). In most situations, the hardness of silicones used increased after 252 hours (p < 0.05). The nonpigmented MDX4-4210 group and all A-2186 groups showed an increase in tear strength after 252 hours (p < 0.05). For the nonpigmented MDX4-4210 group, from 252 to 1008 hours, there was no change in tear strength (p > 0.05). All pigmented MDX4-4210 groups showed no change in tear strength from 0 (initial) to 1008 hours of aging (p > 0.05). In all A-2186 groups, from 252 to 504 hours, there was a reduction in tear strength (p < 0.05), and from 504 to 1008 hours, there was an increase in tear strength (p < 0.05), except in the bronze A-2186 group (p > 0.05). CONCLUSION: In most situations, the A-2186 silicone showed significantly higher values of hardness and tear strength than the MDX4-4210 silicone. All hardness values were considered clinically acceptable. Accelerated aging could increase, decrease, or not significantly change the hardness and tear strength of the silicones used. The results of hardness and tear strength suggest that MDX4-4210 was more influenced by the presence of pigmentation after aging.

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BACKGROUND: Different ceramic surface cleaning methods have been suggested after the acid conditioning. The aim was to evaluate the effect of different protocols used to remove the remaining hydrofluoric acid on the shear bond strength (SBS) between lithium disilicate and resin cement. MATERIAL AND METHODS: Forty-four specimens of lithium disilicate (IPS e.max Press) were divided in 4 groups (n=11): group C (control, no treatment); group HF+S (5% hydrofluoric acid + silane); group HF+US+S (5% hydrofluoric acid + ultrasound cleaning + silane); group HF+PH+S (5% hydrofluoric acid + 37% phosphoric acid + silane). Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were performed to characterize the surface morphology. The SBS test was performed on the resin/ceramic interface, and the failure mode was characterized. SBS values were submitted to 1-way ANOVA and the Tukey test (α=.05). The relation between surface treatment and failure modes was analyzed using the chi-squared test (α=.05). RESULTS: The surface treatment type interfered in the shear strength (p<.001) and higher SBS values were observed for the groups HF+US+S (17.87 MPa) and HF+PH+S (16.37 MPa). The surface treatment did not influence the failure mode (p=.713). No fluorsilicate salts were observed after ultrasound cleaning. CONCLUSIONS: The utilization of ultrasound cleaning was an effective procedure to remove remaining fluorsilicate salts, promoting the highest SBS values. Key words:Bond strength, ceramics, fluorsilicate, lithium disilicate, resin cement.

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AIM: To evaluate the cytotoxicity and inflammatory response of different types of provisional restorative materials to mice gingival fibroblasts. METHODS: Cytotoxicity of provisional material discs (thermal-polymerized acrylic resin; auto-polymerized acrylic resin; bisacrylic resin; nano-ceramic resin for CAD/CAM and prefabricated polymer block for CAD/CAM) to Mice (Balb/c) gingival cell were investigated under direct and indirect contact (extracts) at 24, 48 and 72 h, using the MTT and Alamar blue assays. Materials extracts (24 h) were applied to the cell culture (indirect contact) or cells were seeded on discs of provisional materials, and the cytotoxicity and production of IL-6, IL-1ß and TNF-α after 24, 48 and 72 h were analyzed through MTT, Alamar Blue® and ELISA. Culture medium was used as control for indirect contact assay (extract) and the surfaces of the wells without discs of provisional materials were used as control for direct contact assay. Results were analysed statistically by ANOVA followed by the Bonferroni-Test correction. Statistically significant differences were considered if P was < .05. RESULTS: Auto-polymerized and bisacrylic resins (direct contact) reduced cell viability after 24, 48 and 72 h compared to control (P < .05). Indirect contact (extract) was not cytotoxic to cells at all periods compared to control (P > .05). Auto-polymerized and bisacrylic resins increased IL-6, IL-1ß and TNF-α levels mainly at 24 h when compared to the other materials (P < .001). CONCLUSION: Auto-polymerized and bisacrylic were more cytotoxic to mice gingival fibroblasts. CAD/CAM nano ceramic resin and prefabricated polymer blocks are more predictable materials to preserve the periodontal soft tissues.

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BACKGROUND: The aim of this study was to evaluate the distribution of stress in complete fixed mandibular prostheses with infrastructures (IE) fabricated with different materials and techniques, under compressive force. MATERIAL AND METHODS: A model of an edentulous mandible, which received five 4x11 mm external hexagon implants between the mental foramens, was fabricated. The groups were divided into: Group I - IE in nickel-chromium with an acrylic resin occlusal coating; Group II - IE in nickel-chromium with a ceramic occlusal coating; Group III - IE milled in zirconia with a ceramic coating. For the photoelastic methodology, 70 N axial loads were applied in three regions. Photographic images were taken and analyzed according to the number of high-intensity fringes. For the strain gauge methodology, the measurement of stresses was performed in two distinct regions. The same compression tests described earlier were then performed. The registered stress values were grouped in tables and submitted to two-factor variance analysis (ANOVA) and the Tukey test with 5% significance. RESULTS: The results of the two methodologies demonstrated smaller stress values for Group I, when compared to the other groups. CONCLUSIONS: It was possible to conclude that the complete fixed prostheses, with infrastructures cast in metal and acrylic occlusal coating, demonstrated better biomechanical results. Key words:Dental implants, mandibular prosthesis implantation, biomechanics.

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Para alcançar a estética em dentes anteriores deve-se ter conhecimento de diversas técnicas e principalmente fazer a escolha correta dos materiais. As cerâmicas odontológicas estão cada vez mais presentes nas restaurações, visto que possuem ótimas propriedades ópticas e mecânicas. Assim, o objetivo deste estudo foi proporcionar a estética em dentes anteriores com diferentes subtratos através de uma prótese fixa metal-free. Paciente do gênero masculino, 38 anos, procurou atendimento queixando-se da estética do seu sorriso. No exame clínico foi observada uma coroa total metalocerâmica no elemento 21 e facetas de resina composta nos elementos 11,12 e 22, todas com estética insatisfatória. O dente 21 apresentava um núcleo metálico fundido adequado e os dentes 12 e 22 com tratamentos endodônticos. Foi proposta a instalação de pinos de fibra de vidro nos dentes 12 e 22. Além, da confecção de coroas totais metais-free em dissilicato de lítio nos quatro incisivos superiores com o sistema e-max ceram. O resultado final estético e funcional foi aprovado pelo paciente e pelos profissionais envolvidos(AU)

To achieve aesthetics in anterior teeth one must be aware of several techniques and especially make the correct choice of materials. Dental ceramics are increasingly present in restorations, since they have excellent optical and mechanical properties. Thus, the objective of this study was to achieve esthetics in anterior teeth with different substrate through a fixed prosthesis metal-free. A male patient, 38 years old, sought care complaining about the aesthetics of his smile. In the clinical examination a total metaloceramic crown was observed in element 21 and composite resin facets in elements 11,12 and 22, all with unsatisfactory aesthetics. Tooth 21 had a suitable molten metal core and teeth 12 and 22 with endodontic treatments. It was proposed to install fiberglass pins on the teeth 12 and 22. In addition, from the manufacture of total metal-free crowns in lithium disilicate in the four upper incisors with the e-max system ceram. The final aesthetic and functional result was approved by the patient and the professionals involved(AU)

Para alcanzar la estética en dientes anteriores se debe tener conocimiento de diversas técnicas y principalmente hacer la elección correcta de los materiales. Las cerámicas dentales están cada vez más presentes en las restauraciones, ya que poseen óptimas propiedades ópticas y mecánicas. Así, el objetivo de este estudio fue proporcionar la estética en dientes anteriores con diferentes sustratos a través de una prótesis fija metal-free. Paciente del género masculino, 38 años, buscó atención quejándose de la estética de su sonrisa. En el examen clínico se observó una corona total metalocerámica en el elemento 21 y facetas de resina compuesta en los elementos 11,12 y 22, todas con estética insatisfactoria. El diente 21 presentaba un núcleo metálico fundido adecuado y los dientes 12 y 22 con tratamientos endodónticos. Se propuso la instalación de pines de fibra de vidrio en los dientes 12 y 22. Además, de la confección de coronas totales metales libres en disilicato de litio en los cuatro incisivos superiores con el sistema e-max ceram. El resultado final estético y funcional fue aprobado por el paciente y los profesionales involucrados(AU)

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Devido a evolução dos sistemas cerâmicos, atualmente, são permitidas inúmeras associações de materiais restauradores. Entretanto, mimetizar as características visuais das próteses livres de metal com próteses metalocerâmica permanece um desafio. Assim, o objetivo deste trabalho foi relatar o caso clínico de substituição de próteses desadaptadas, homogeneizando próteses parciais fixas livres de metal e metalocerâmicas dento e implantossuportadas, após cirurgia periodontal. O paciente de 55 anos, gênero masculino, compareceu à Clínica de Prótese Parcial Fixa, da Faculdade de Odontologia de Araçatuba ­ FOA/UNESP em 2017 queixando-se dos seus dentes anteriores estarem "feios" e com a "raiz aparecendo". No exame clínico foi constatada recessão gengival nos elementos 11 e 13, os quais continham uma prótese parcial fixa de três elementos metalocerâmicas desadaptada, prótese sobre implante nos elementos 21 e 22, que apresentavam-se desadaptadas e com estética desfavorável. No exame radiográfico pôde-se observar a presença de um núcleo metálico fundido nos elementos 11 e 13. Foi proposto, então, a confecção de coroas totais livres de metal nos elementos anteriores superiores (13, 12, 11, 21 e 23) e coroa metalocerâmica para o elemento 22. Para isso, foi realizado enceramento diagnóstico inicial e, após o consentimento do paciente, foi efetuada a remoção das próteses antigas. Com a remoção, visualizamos uma . depressão na vestibular do rebordo na área do 12 (ausente), solucionado com um enxerto gengival subepitelialApós a realização dos preparos dentários e moldagem com silicone de adição as peças foram confeccionadas com sistema e.max Ceram (Ivoclar Vivadent). Após a prova estética e ajustes oclusais iniciais, as peças foram preparadas para cimentação resinosa com o sistema Variolink® N (Ivoclar Vivadent). O cimento transparente Conclui-se que, apesar da disparidade dos materiais, é possível mimetizá-los e foi selecionado previamente por meio de provas com o kit Try-In.oferecer resultados reabilitadores suficientemente estéticos e satisfatórios(AU)

Due to the evolution of ceramic systems, numerous associations of restorative materials are now permitted. However, mimicking the visual characteristics of metal-free prostheses with metal-ceramic dentures remains a challenge. Thus, the objective of this study was to report the clinical case of replacement of maladaptive dentures, homogenizing denture free and fixed metal partial dentures and implants supported after periodontal surgery. The patient, 55 years old, male, attended the Fixed Partial Prosthesis Clinic of the Faculty of Dentistry of Araçatuba - FOA / UNESP in 2017 complaining that his anterior teeth were "ugly" and with the "root appearing". In the clinical examination, gingival recession was observed in elements 11 and 13, which contained a fixed partial prosthesis of three maladaptive metal-ceramic elements, a prosthesis on implants in elements 21 and 22, the prostheses were maladapted and unfavorable esthetics. In the radiographic examination it is possible to observe the presence of a molten metal nucleus in elements 11 and 13. It was proposed, then, the manufacture of free metal crowns in the upper anterior elements (13, 12, 11, 21 and 23) and crown PFM for the element 22. For this, it performed waxing initial diagnosis and after the patient's consent, the removal of the old prosthesis were performed. Upon removal, a depression visualize the buccal flange in the area 12 (absent), solved with a subepithelial gum graft. After the dental preparations and molding with silicone of addition the pieces were made with e.max Ceram system (Ivoclar Vivadent). After the initial test and aesthetic occlusal adjustments, the pieces were prepared for cementing with resin Variolink® N system (Ivoclar Vivadent). The clear cement was previously selected by the test realized with Try-In kit. We conclude that, despite the disparity of materials, it is possible to mimic them and offer rehabilitative results sufficiently aesthetic and satisfactory(AU)

Debido a la evolución de los sistemas cerámicos, actualmente, se permiten numerosas asociaciones de materiales restauradores. Sin embargo, mimetizar las características visuales de las prótesis libres de metal con prótesis metalocerámicas sigue siendo un desafío. Así, el objetivo de este trabajo fue relatar el caso clínico de sustitución de prótesis desadaptadas, homogeneizando prótesis parciales fijas libres de metal y metalocerámicas dento e implantosuportadas, después de cirugía periodontal. El paciente de 55 años, género masculino, asistió a la Clínica de Prótesis Parcial Fija, de la Facultad de Odontología de Araçatuba - FOA / UNESP en 2017 quejándose de sus dientes anteriores estar "feos" y con la "raíz apareciendo". En el examen clínico se constató recesión gingival en los elementos 11 y 13, los cuales contenían una prótesis parcial fija de tres elementos metalocerámicos desadaptados, prótesis sobre implante en los elementos 21 y 22, las prótesis se presentaban desadaptadas y con estética desfavorable. En el examen radiográfico se puede observar la presencia de un núcleo metálico fundido en los elementos 11 y 13. Se propuso entonces la confección de coronas totales de metal en los elementos anteriores superiores (13, 12, 11, 21 y 23) y corona metalocerámica para el elemento 22. Para ello, se realizó el encerado diagnóstico inicial y, tras el consentimiento del paciente, se efectuó la remoción de las prótesis antiguas. Con la remoción, visualizamos una depresión en la vestibular del borde en el área del 12 (ausente), solucionado con un injerto gingival subepitelial. Después de la realización de los preparados dentales y moldeo con silicona de adición las piezas fueron confeccionadas con sistema e.max Ceram (Ivoclar Vivadent). Después de la prueba estética y ajustes oclusales iniciales, las piezas fueron preparadas para cementación resinosa con el sistema Variolink® N (Ivoclar Vivadent). El cemento transparente fue seleccionado previamente por medio de pruebas con el kit Try-In. Se concluye que, a pesar de la disparidad de los materiales, es posible mimetizarlos y ofrecer resultados rehabilitadores suficientemente estéticos y satisfactorios(AU)

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In some clinical situations, the clinician may encounter previously installed implants that should be associated with other implants for a proper rehabilitation. The aim of this study was to evaluate the biomechanical behaviour of a multiple prosthesis joined by different implant connections using photoelasticity. Photoelastic models with a screwed fixed prosthesis supported by implants with different connection systems (Morse taper, external hexagon, internal hexagon, and Flexcone), and different combinations among them, were fabricated. Each assembly was placed in a circular polariscope, and axial and oblique (45°) loads of 100 N were applied on the occlusal surface of the crowns. The fringe patterns were photographed and the analysis was performed by counting the number of high-intensity fringes and also according to the stress distribution region where they appeared. Among implants of the same connection, the external connections obtained a greater number of high intensity fringes when compared to the internal connections. From the biomechanical point of view, the association between different types of connections obtained positive results.

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PURPOSE: The objective of this systematic review with meta-analysis was to evaluate surface treatment in yttria-stabilized tetragonal zirconia polycrystal ceramic (Y-TZP) on the shear bond strength (SBS) values between Y-TZP (core ceramic) and veneer ceramic, compared to untreated specimens. MATERIALS AND METHODS: This review was registered at PROSPERO platform under the number CRD42016036493. The systematic review of the extracted publications was performed to compare the effect of surface treatment on SBS between Y-TZP ceramic and veneering ceramic. A comprehensive review of the literature from the earliest available dates through January 2017 was performed in the PubMed/Medline, Embase, Scopus, and Cochrane Library databases. RESULTS: A total of 15 studies were identified for the inclusion of data, with only in vitro studies. A random-effect model found statistically significant differences between untreated and treated surfaces of Y-TZP (p < 0.00001; MD: 2.84; 95% CI: 2.19 to 3.49). In another analysis, a random-effect model found statistically significant differences between the groups that only performed the associations of treatments and control group (p < 0.00001; MD: 3.19; 95% CI: 2.11 to 4.28). CONCLUSIONS: Surface treatment in Y-TZP improved the values of SBS between the Y-TZP and veneer ceramic. The associations between two or more treatments also showed positive effect on the bond strength due the cumulative effect of the treatments.

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Evaluate the color stability of facial silicone pigmented extrinsically under the influence of the hygiene process. Methods: 160 samples were prepared and divided into 8 groups (n = 20) according to the pigmentation technique used: Group 1: Colorless silicone; Group 2: Pigmented exclusively with oil ink; Group 3: Pigmented with oil ink + opacifier; Group 4: Colorless, applying Prime; Group 5: Pigmented with oil ink covered with Prime; Group 6: Pigmented with oil ink + opacifier and covered with Prime; Group 7: Pigmented with oil ink diluted in Prime; Group 8: Pigmented with oil ink + opacifier diluted in Prime. Then the samples were distributed into two subgropus (n=10): 1: neutral soap and 2: 1% hypochlorite solution. The color readings occurred in the initial period and 60 days after the hygiene procedures. For this, it was used a spectrophotometer reflection and CIE-Lab program. The data was tabulated and submitted to analysis of variance (ANOVA) followed by Tukey test (p <0.05). Results: The groups of samples disinfected with soap showed significantly lower color change values than those presented by the samples disinfected with hypochlorite. The best results were presented by the group of samples pigmented with oil ink diluted in prime and sanitized with neutral soap (ΔE=1.21, without opacifier and ΔE=0.82, with opacifier). Conclusions: The association of oil ink diluted in prime and hygiene technique with soap promotes the lower color change of facial silicone pigmented extrinsically

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PURPOSE: The aim of this study was to assess stress distribution in the bone-implant interface of a mandibular implant-supported prosthesis with different cantilever lengths, aesthetic coating materials, and implant abutments. MATERIALS AND METHODS: A photoelastic model of an edentulous mandible, containing 5 external hexagon implants, was constructed. Experimental models were divided into 6 groups: group 1-UCLA component and metal bar; group 2-UCLA component and acrylic resin coating; group 3-UCLA component and porcelain coating; group 4-abutment and metal bar; group 5-abutment and acrylic resin coating; and group 6-abutment and porcelain coating. Forces were applied to the most anterior implant, the most posterior implant, and different cantilever lengths. RESULTS: The results showed a higher number of high-stress fringes as the cantilever length increased. Fringes were better distributed in groups with prostheses composed of acrylic resin and in groups that contained an abutment. CONCLUSION: The stress distribution in the bone-implant interface is improved when the cantilever is eliminated and when abutments in an acrylic resin prosthesis are used.

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